package servlets;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;

/**
 * Servlet Filter implementation class ProfilerFilter
 */
@WebFilter("/ProfilerFilter")
public class ProfilerFilter implements Filter {
	private FilterConfig fConfig;
    /**
     * Default constructor. 
     */
    public ProfilerFilter() {
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see Filter#destroy()
	 */
	public void destroy() {
		// TODO Auto-generated method stub
	}

	/**
	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
	 */
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
		long start = System.currentTimeMillis();	// PRE-P.
		chain.doFilter(request, response);
		long ende = System.currentTimeMillis();		// POST-P.
		if(request instanceof HttpServletRequest)
			this.fConfig.getServletContext().log("Dauer: "+(ende-start)
		+" ms, URI: "+((HttpServletRequest)request).getRequestURI());
	}

	/**
	 * @see Filter#init(FilterConfig)
	 */
	public void init(FilterConfig fConfig) throws ServletException {
		this.fConfig = fConfig;
	}

}
